Graphical user interface for a display screen or portion thereof



FIG. 1 is a front view of a graphical user interface for a display screen or portion thereof showing my new design;

FIG. 2 is a front view of a second embodiment thereof; and,

FIG. 3 is a front view of a third embodiment thereof.

The broken line showing of the display screen or portion thereof forms no part of the claimed design.

The Google trademark in the lower left corner of the Figures is the property of Google Inc. The AT&T trademark in the upper left corner of the Figures is the property of AT&T. All trademarks are the property of their respective owners. 

The ornamental design for a graphical user interface for a display screen or portion thereof, as shown and described. 